KR20110082191A - Methods and systems for inter-rat handover in multi-mode mobile station - Google Patents

Abstract

Methods and systems for handover between RATs in a multi-mode mobile station may send a request message indicating a set of multiple-input multiple-output (MIMO) resources to reallocate to a base station (BS) of the first RAT. Transmitting to; During a scan duration, communicating with the BS of the first RAT using non-reallocated MIMO resources, and communicating with the BS of the second RAT using reallocated MIMO resources ; And during normal duration, communicating with the BS of the first RAT using the reallocated MIMO resources and the unallocated MIMO resources. The apparatus provided includes logic for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation; During scan duration, logic to communicate with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And logic for communicating with the MS in a second transmission mode assuming use of the reallocated MIMO resources and the unallocated MIMO resources by the MS during a regular duration.

Description

METHODS AND SYSTEMS FOR INTER-RAT HANDOVER IN MULTI-MODE MOBILE STATION}

TECHNICAL FIELD The present disclosure relates generally to communications, and more specifically, to a method for reallocating resources in a mobile station multiple-input multiple-output to provide operation for communication between WiMAX and another radio access technology (RAT). It is about providing.

This application is filed on November 6, 2008, and entitled "Method and Apparatus for Smooth Inter-RAT Handover with Reduced MIMO Capability for Multi-Mode WiMAX Mobile Station", and is filed by US Provisional Application No. 61 / 112,139. Claiming the benefit of priority, the provisional application is assigned to the assignee of the present application and incorporated herein by reference in its entirety for all purposes.

In a WiMAX system, a mobile station (MS) may support multiple-input multiple-output (MIMO) operations, where the MS may have multiple transmit and receive antennas.

In order to support smooth handover between the WiMAX network and other RATs such as CDMA and UMTA, circuitry may be provided to the MS that allows simultaneous transmission and reception of multiple RATs. Unfortunately, this involves the wireless hardware of multiple sets of MSs, which increases cost and power consumption. In order to support multiple RATs with a single set of wireless hardware, WiMAX supports a scanning mode in which the MS is allowed to leave the WiMAX network.

Unfortunately, scanning interferes with any active WiMAX service, so as with conventional scanning, the MS cannot transmit and receive using the WiMAX network.

Certain embodiments provide a method for communicating using a first radio access technology (RAT) and a second RAT. The method generally includes sending a request message to a base station (BS) of a first RAT indicating an indicating set of multiple-input multiple-output (MIMO) resources for reallocation; During a scan duration, communicating with the BS of the first RAT using non-reallocated MIMO resources, and communicating with the BS of the second RAT using reallocated MIMO resources ; And during normal duration, communicating with the BS of the first RAT using the reallocated MIMO resources and the unallocated MIMO resources.

Certain embodiments provide a method for communicating with a mobile station (MS). The method generally includes receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation; During a scan duration, communicating with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And during normal duration, communicating with the MS in a second transmission mode assuming the use of reallocated and unallocated MIMO resources by the MS.

Certain embodiments provide an apparatus for communicating using a first RAT and a second RAT. The apparatus generally includes logic for sending a request message to a base station (BS) of the first RAT indicating a set of multiple-input multiple-output (MIMO) resources for reallocation; During scan duration, logic for communicating with the BS of the first RAT using unallocated MIMO resources and communicating with the BS of the second RAT using reallocated MIMO resources; And logic for communicating with the BS of the first RAT during the normal duration using the reallocated MIMO resources and the unallocated MIMO resources.

Certain embodiments provide an apparatus for communicating with an MS. The apparatus generally includes logic for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation; During scan duration, logic to communicate with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And logic for communicating with the MS in a second transmission mode assuming the use of the reallocated MIMO resources and the reallocated MIMO resources by the MS during a normal duration.

Certain embodiments provide an apparatus for communicating using a first RAT and a second RAT. The apparatus generally includes means for sending a request message to a base station (BS) of the first RAT indicating a set of multiple-input multiple-output (MIMO) resources for reallocation; During scan duration, means for communicating with the BS of the first RAT using unallocated MIMO resources and with the BS of the second RAT using reallocated MIMO resources; And means for communicating with the BS of the first RAT during the normal duration using the reallocated MIMO resources and the unallocated MIMO resources.

Certain embodiments provide an apparatus for communicating with an MS. The apparatus generally includes means for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS to reallocate; During scan duration, means for communicating with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And means for communicating with the MS in a second transmission mode assuming the use of reallocated and unallocated MIMO resources by the MS during a normal duration.

Certain embodiments provide a computer-program storage device for communicating using a first radio access technology (RAT) and a second RAT, wherein the computer-program storage device is capable of executing stored instructions that can be executed by one or more processors. Computer-readable media having the set. The set of instructions generally includes instructions for sending a request message to a base station (BS) of the first RAT indicating a set of multiple-input multiple-output (MIMO) resources for reallocation; During scan duration, instructions for communicating with the BS of the first RAT using unallocated MIMO resources and with the BS of the second RAT using reallocated MIMO resources; And instructions for communicating with a BS of the first RAT during the normal duration using the reallocated MIMO resources and the unallocated MIMO resources.

Certain embodiments provide a computer-program storage device for communicating with a mobile station (MS), wherein the computer-program storage device includes a computer-readable medium having a set of stored instructions that can be executed by one or more processors. . The set of instructions is generally an instruction for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation. field; During a scan duration, instructions for communicating with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And during normal duration, instructions for communicating with the MS in a second transmission mode assuming the use of reallocated MIMO resources and the unallocated MIMO resources.

Aspects and embodiments of the present disclosure will become more apparent from the detailed description set forth below when judged in conjunction with the drawings, and like reference numerals in the drawings are considered to be identical to corresponding reference numerals throughout the document.
1 illustrates an example wireless communication system in accordance with certain embodiments presented herein.
2 illustrates an example wireless network environment, in accordance with certain embodiments presented herein.
3 illustrates allocation of example resources in accordance with certain embodiments presented herein.
4 illustrates allocation of example resources in accordance with certain embodiments presented herein.
5 illustrates allocation of example resources in accordance with certain embodiments presented herein.
6 illustrates example operations performed at an MS in accordance with certain embodiments presented herein.
7 illustrates example means for communicating with a BS in accordance with certain embodiments presented herein.
8 illustrates example operations performed by a BS in accordance with certain embodiments presented herein.
9 illustrates example means for communicating with an MS in accordance with certain embodiments presented herein.
10 is an example exchange of instructions between a BS and an MS of a WiMAX network, an example exchange of instructions between a BS and an MS of a second RAT, and performed by an MS, in accordance with certain embodiments presented herein. Illustrative operations are illustrated.

Specific embodiments are described herein with reference to the drawings, wherein like reference numerals are used to refer to like elements. In the following description, for purposes of illustration, numerous specific details are set forth in order to provide a thorough understanding of certain embodiments. However, such embodiments may be practiced without these specific details. In other instances, known structures and devices are shown in block diagram form in order to facilitate describing particular embodiments.

Example Wireless Communication System

The techniques described herein may be used in a variety of broadband wireless communication systems, including communication systems based on an orthogonal multiplexing scheme. Examples of such communication systems include orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and the like. An OFDMA system uses Orthogonal Frequency Division Multiplexing (OFDM), a modulation technique that divides the overall system bandwidth into multiple orthogonal sub-carriers. Such sub-carriers may also be referred to as tones, bins, and the like. Using OFDM, each sub-carrier can be independently modulated with data. SC-FDMA systems can use interleaved FDMA (IFDMA) to transmit on sub-carriers distributed over system bandwidth, or use localized FDMA (LFDMA) to transmit on blocks of adjacent sub-carriers. Or may use enhanced FDMA (EFDMA) to transmit on multiple blocks of adjacent sub-carriers. In general, modulation symbols are sent in the time domain using SC-FDMA and in the frequency domain using OFDM.

An example of a communication system based on orthogonal multiplexing is a WiMAX system. Worldwide Interoperability for Microwave Access (WiMAX) is a standards-based broadband wireless technology that provides high-throughput broadband connections over long distances. There are two main applications for WiMAX today: fixed WiMAX and mobile WiMAX. Fixed WiMAX applications are point-to-multipoint, enabling broadband access to home and work, for example. Mobile WiMAX is based on OFDM and OFDMA and provides full mobility of cellular networks at broadband speeds.

IEEE 802.16x is an emerging standards body for defining air interfaces for fixed and mobile broadband wireless access (BWA) systems. These standards define at least four different physical layers (PHYs) and one medium access control (MAC) layer. Of the four physical layers, the OFDM and OFDMA physical layers are most popular in each of the fixed and mobile BWA regions.

1 illustrates an example wireless communication system 100 in accordance with certain embodiments presented herein. The wireless communication system 100 may be a broadband wireless communication system. The term “broadband wireless” refers to a technology that provides at least wireless, audio, video, voice, internet, and / or data network access. The wireless communication system 100 provides communication for one or more cells 102, each of which is serviced by a base station 104. Base station 104 may be a fixed station that communicates with user terminals 106 in a cell 102 serviced by the base station 104. Base station 104 may alternatively be referred to as an access point, Node B, or some other terminology.

As shown in FIG. 1, various users 106 are distributed throughout the wireless communication system 100. The user terminals 106 may be stationary (ie, stationary), mobile or both. User terminals 106 may alternatively be referred to as remote stations, access terminals, terminals, subscriber units, mobile stations, stations user equipment, and the like. User terminals 106 may include cellular telephones, personal digital assistants (PDAs), handheld devices, wireless modems, audio / video players, laptop computers, personal computers, other handheld communication devices, Personal wireless devices such as other handheld computing devices, satellite radios, global positioning systems, and the like. Various algorithms and methods may be used for transmissions between base stations 104 and user terminals 106 in the wireless communication system 100. For example, signals may be transmitted and received between base stations 104 and user terminals 106 in accordance with OFDM / OFDMA techniques. In such a case, the wireless communication system 100 may be referred to as an OFDM / OFDMA system 100.

The communication link that facilitates transmission from the base station 104 to the user terminal 106 may be referred to as a downlink 108, and the communication link that facilitates transmission from the user terminal 106 to the base station 104 may be referred to as a downlink 108. It may be referred to as uplink 110. Alternatively, downlink 108 may be referred to as a forward link or forward channel, and uplink 110 may be referred to as a reverse link or reverse channel. Cell 102 may be divided into a number of sectors 112. Sector 112 is a physical coverage area within cell 102. Base stations 104 in OFDM / OFDMA system 100 may use antennas to concentrate the flow of power within a particular sector 112 of cell 102. Such antennas may be referred to as directional antennas.

In certain embodiments, system 100 may be a multiple-input multiple-output (MIMO) communication system. In addition, the system 100 may use virtually any type of duplex technique to partition communication channels (eg, forward link 108, reverse link 110, etc.), such as FDD, TD, and the like. Channels may be provided for transmitting control data between mobile devices 106 and respective base stations 104.

2 illustrates an example wireless network environment 200 in accordance with certain embodiments presented herein. The wireless network environment 200 represents one base station 210 and one mobile device 250 for simplicity. However, system 200 may include one or more base stations and / or one or more mobile devices, where additional base stations and / or mobile devices are shown herein as illustrated base station 210 and illustrated mobile device ( It is contemplated that it may be substantially similar to or different from 250). In addition, the systems, techniques, configurations, and embodiments in which base station 210 and / or mobile device 250 are described herein to facilitate wireless communication between base station 210 and mobile device 250. It is contemplated that aspects, and / or methods, may be used.

At base station 210, traffic data for multiple data streams is provided from data source 212 to transmit data processor 214. In certain embodiments, each data stream may be transmitted through each antenna and / or through multiple antennas. TX data processor 210 formats, codes, and interleaves the traffic data stream based on a particular coding scheme selected for the data stream to provide coded data.

The coded data for each data stream may be multiplexed with pilot data using, for example, orthogonal frequency division multiplexing (OFDM) techniques. Additionally or alternatively, the pilot symbols may be frequency division multiplexed (FDM), time division multiplexed (TDM) or code division multiplexed (CDM). Pilot data is typically a known data pattern that is processed in a known manner and can be used at mobile device 250 to estimate channel response or other communication parameters and / or characteristics. A particular modulation scheme selected for the data stream to provide modulation symbols (e.g., binary phase-shifted modulation (BPSK), quadrature phase-shifted modulation (QPSK), M-phase-shifted modulation (M-PSK) multiplexed pilot and coded data may be modulated (ie, symbols are mapped) for each data stream based on -shift keying), or M- quadrature amplitude modulation (M-QAM). For each data stream, the data rate, coding, and modulation may be determined by the instructions provided or performed by the processor 230.

Modulation symbols for the data streams may be provided to the TX MIMO processor 220, which may further process the modulation symbols (eg, for OFDM). TX MIMO processor 220 then provides N _T modulation symbol streams to N _T transmitters (TMTR) 222a through 222t. In certain embodiments, TX MIMO processor 220 applies certain multi-antenna techniques such as spatial multiplexing, diversity coding or precoding (ie, beamforming the modulation symbols and antennas of the data streams). apply beamforming weights, and symbols are transmitted from the antennas.

Each transmitter 222 receives and processes each symbol stream to provide one or more analog signals, further conditioning (eg, amplifying, filtering) the analog signals to provide a modulated signal suitable for transmission on a MIMO channel. , And upconvert). Next, from a transmitter (222a to 222t) N _T modulated signals are transmitted from each of the N _T antennas (224a to 224t).

At mobile device 250, the modulated signals transmitted are received by N _R antennas 252a through 252r and the signal received from each antenna 252 to each receiver (RCVR) 254a through 254r. Is provided. Each receiver 254 conditions (eg, filters, amplifies, and downconverts) each received signal, digitizes the conditioned signal to provide samples, and generates a corresponding " received " symbol stream. The samples are further processed to provide.

RX data processor 260 N _T of "detected (detected)", based on a particular receiver processing technique to provide symbol stream receives the N _R received symbols streams from N _R receivers 254 and processing do. RX data processor 260 demodulates, deinterleaves, and / or decodes each detected symbol stream to recover traffic data for the data stream. In certain embodiments, for mobile device 250, the processing by RX data processor 260 may be complementary to the processing performed by TX MIMO processor 220 and TX data processor 214 at base station 210. Can be.

Processor 270 may periodically determine which pre-coded matrix to use as discussed above. Further, processor 270 may formulate a reverse link message having a matrix index portion and a rank value portion. The reverse link message may comprise various types of information regarding the communication link and / or the received data stream. It may include. The reverse link message may be processed by the TX data processor 238 which also receives multiple data streams from the data source 236, may be modulated by the modulator 280, and sent to the transmitters 254a through 254r. And may be sent back to the base station 210.

At base station 210, modulated signals from mobile device 250 are received by antennas 224, conditioned by receivers 222, modulated by modulator 240, and RX data processor 242. ) Extracts the reverse link message sent by the mobile device 250, and provides the reverse link message to the data sink 244. Further, processor 230 may process the extracted message to determine which precoded matrix to use to determine beamforming weights.

Processors 230 and 270 may direct (eg, control, coordinate, manage, etc.) operation at base station 210 and mobile device 250, respectively. Respective processors 230 and 270 may be associated with memories 232 and 272 that store program codes and data. Processors 230 and 270 may also perform calculations to derive frequency and impulse response estimates for the uplink and downlink, respectively. All “processor” functions may vary between processor modules such that specific processor modules may not be presented in certain embodiments or additional processor modules not shown herein may be presented.

Memory 232 and 272 (including all data stores disclosed herein) may be volatile memory or nonvolatile memory or may include both volatile and nonvolatile portions, and may be fixed or removable, or It can include both fixed and removable portions. For example, nonvolatile memory may include, but is not limited to, read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable PROM (EEPROM), or flash memory. It doesn't happen. Volatile memory can include random access memory (RAM), which can act as an external cache memory. For example, RAM includes synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double-speed SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM. (SLDRAM), and direct rambus RAM (DRRAM) are available in many forms, but are not limited to these. The memory 232 and 272 of certain embodiments is intended to include, but is not limited to, these and any other suitable types of memory.

Multi- mode In mobile stations RAT  Illustrative of the liver Handover

In accordance with certain embodiments of the present disclosure, a multi-mode MS provides operation for handover between a first RAT (eg WiMAX) and a second RAT (eg CDMA or UMTS), It may be configured to reallocate several MIMO transmit and receive resources. This reassignment allows the MS to perform some less traffic activity, such as handover set up in the second RAT, with less impact on active services in the first RAT. do.

According to certain embodiments of the present application, the MS may negotiate these reduced MIMO capacity modes and associated time intervals with less impact on performance while in a traffic mode in a WiMAX network. As a result, handover reliability and interruption can be significantly improved.

Reassignment may allow the MS to perform functions associated with the second RAT while in the traffic mode of the WiMAX network. These functions include measuring the signal strength of the second RAT (receive), obtaining the timing of the second RAT (receive), obtaining system overhead messages of the second RAT (receive), and the second RAT. Exchanging signaling messages or data with (eg, handover signaling to a second RAT) (sending and receiving).

It can be noted that these functions only require transmitting or receiving a small amount of data, which may require less processing power. In addition, in certain embodiments, the second RAT may not require MIMO capability, such that reallocation of MIMO resources may not significantly affect communication with the WiMAX BS. Other functions are also possible that may require a small or large amount of data using the second RAT.

3 illustrates an example of certain embodiments of the present disclosure. In configuration 1 of FIG. 3, the MS 300 has two transmit MIMO resources 302 and two receive MIMO resources 304 for communication with the WiMAX BS 306 in MIMO mode. In the scanning interval, the MS 300 may switch to configuration 2 of FIG. 3. In configuration 2, the MS 300 is shown to include one transmitting MIMO resource 302 and one receiving MIMO resource 304 in communication with the WiMAX BS 306. One transmitting MIMO resource 302 ′ and one receiving MIMO resource 304 ′ are shown to be reallocated for communication with the second RAT 308. For example, the MS measures the signal strength to prepare for handover and / or exchanges signaling messages with the second RAT base station 308 to receive MIMO resource 302 'and receive MIMO resource 304'. Can be used. The second RAT base station 208 can be part of a CDMA network, a UMTS network, or any other RAT network. The processor 310 for providing a MAC or Layer 3 protocol stack may be loaded into the firmware and software of both RATs even if the baseband and RF hardware can be separated.

4 illustrates certain embodiments for reallocating MIMO resources, in accordance with aspects of the present disclosure. The example shown assumes that the MS has M transmit resources and N receive resources.

In FIG. 4, the MS may have negotiated reduced MIMO capability with the first RAT. For example, the MS may have sent a MOB_SCN-REQ message to the WiMAX BS to request when the MS can reduce the MIMO capability to perform the operations of the second RAT in frame 402. As shown in FIG. 4, the MS may transmit and receive with reduced MIMO capability (M-1 transmission and N-1 reception, as shown) during the WiMAX network and scanning durations 404. This allows the MS to maintain communication with the first RAT without significant loss of throughput while performing light operations 406 with the second RAT, such as sending and receiving signaling messages for handover. In normal duration, or between two scan durations, the MS can still operate in the WiMAX network with full MIMO capability (M transmits and N receive) as usual.

As an example for certain embodiments, the following message change in MOB_SCN-REQ will allow negotiation for this reduced MIMO capability mode and associated time intervals:

name

size
Justice
Remark


Reduced MIMO Ability


8 bit
Bits # 0-3 : # of transmissions in MIMO remaining in the scanning duration

Bits # 4-7 : In Scanning Duration
# Of receptions in the remaining MIMO



Proposed New TLV

If there is no reduced MIMO capability TLV in MOB_SCN-REQ, the WiMAX BS should not transmit or receive during the scanning interval.

If there is a reduced MIMO capability TLV in the MOB_SCN-REQ, the WiMAX BS may continue to transmit or receive data with the MS in reduced MIMO capability at the scanning interval. This may involve a slow overall data transfer rate. However, current standards allow the MS to transmit MPDU in scan duration as implicit signaling to stop scanning. If the MIMO capability TLV is present in the MOB_SCN-REQ, this no longer applies (no longer true). The MS may only send a MOB_SCN-REQ message containing parameter scan duration = 0 to stop the remaining scanning.

As shown in FIG. 5, the MS may need to perform operations in the second RAT during successive intervals. For example, this may be because the BS of the second RAT may transmit the signaling message at any time after the MS sends the request signaling message. Therefore, continuous monitoring with the second RAT may be needed. The MS may request in a MOB_SCN-REQ message that includes a parameter interleaving interval = 0 (ie, no regular interval between scan durations 504 exists).

According to certain embodiments of the present application, since the WiMAX standards allow 255 iterations and allow 255 frames per scan duration, respectively, the MS will wait for 325 seconds (assuming 5ms frame duration: 5ms × 255 × 255). 325 seconds) may continue to operate in this reduced MIMO capability mode, which may be sufficient for the MS to perform the operations 506 required in the second RAT, such as, for example, a smooth handover. have. After the end of all scan iterations, the MS can resume the WiMAX BS and normal MIMO mode at regular interval 508. In certain embodiments, the MS can simply resume communications with the WiMAX BS, for example to negotiate a handover to the second RAT.

6 illustrates an example of operations performed by an MS in accordance with certain embodiments of the present application. At 602, the MS notifies the BS of the first RAT that the MS will reallocate some MIMO transmitting and receiving resources, so that the MIMO capability at the MS is reduced during several intervals. At 604, the MS acknowledges from the BS at the first RAT that some MIMO resources at the MS have been reallocated, such that the BS at the first RAT has the full capability MIMO mode for the MS during several intervals. Receive a message confirming that you do not expect to work on. In scan duration, as shown at 606, the MS communicates with the BS in the first RAT using non-reallocated MIMO resources, and the MS uses the second RAT using the reallocated MIMO resources. Communicate with the BS at In normal duration, as shown at 608, the MS communicates with the BS of the first RAT using reallocated and unallocated MIMO resources.

7 shows examples of means for communicating with a BS in accordance with certain embodiments of the present application. In certain embodiments, the MS includes means for communicating with the BS. As shown at 702, the MS includes means for notifying the BS of the first RAT that it will reassign some MIMO transmitting and receiving resources, such that the MIMO capability at the MS is reduced during several intervals. . At 704, the MS includes means for receiving a response from the BS at the first RAT acknowledging that some MIMO resources at the MS have been re-allocated, such that the BS at the first RAT causes the MS several intervals. Ensure that you do not expect to operate in MIMO mode at full capability during these periods. As shown at 706, the MS communicates with the BS at the second RAT using the reallocated MIMO resources, and means for communicating with the BS at the first RAT during the scan duration. Means for doing so. As shown at 708, the MS also includes means for communicating with the BS of the first RAT in normal duration using reallocated and unallocated MIMO resources.

8 illustrates an example of operations performed by a BS in accordance with certain embodiments of the present application. At 802, the BS receives a message from the MS that the MS will reallocate some MIMO transmitting and receiving resources. At 804, the BS sends a response confirming that the MIMO resources at the MS have been reallocated. As shown at 806, in scan duration, the BS communicates with the MS assuming that the MS's reallocated MIMO resources are not available. As shown at 808, in normal duration, the BS communicates with the MS using reallocated MIMO resources and unallocated MIMO resources.

9 shows examples of means for communicating with an MS in accordance with certain embodiments of the present application. In certain embodiments, the BS in the first RAT includes means for communicating with the MS. As shown at 902, the BS includes means for receiving a message from the MS that the MS will reassign some MIMO transmitting and receiving resources, such that the MIMO capability at the MS is reduced during several intervals. . As shown at 904, the BS includes means for sending a response to the MS acknowledging that some of the MIMO resources of the MS have been reallocated, such that the BS at the first RAT indicates that the MS has a maximum during several intervals. Confirm that you do not expect to operate in MIMO mode of capability. At 906, the BS includes means for communicating with the MS using unallocated MIMO resources in scan duration (ie, assuming that the MS's reallocated MIMO resources are not available). As shown at 908, the BS also includes means for communicating with the MS in normal duration using reallocated and unallocated MIMO resources.

If the MS can complete the handover between RATs earlier than the end of all scan iterations, the MS can abort the remaining scanning by sending MOB_SCN-REQ with parameter scan duration = 0.

In accordance with certain embodiments of the present disclosure, the BS and MS of the WiMAX network may use scanning request and response messages to negotiate a reduced capability mode and associated time intervals.

10 illustrates an example exchange of instructions between BS 1004 and MS 1002 of a WiMAX network, an example exchange of instructions between BS 1006 and MS 1002 of a second RAT, and MS ( Example operations performed by 1002 are shown in accordance with certain embodiments presented herein. For example, FIG. 10 shows that the MS 1002 performs certain functions related to the BS 1006 of the second RAT while continuing to communicate with the BS 1004 of the WiMAX network. While the MS 1002 performs certain functions related to the BS 1006 of the second RAT, the MS 1002 may perform the BS of the WiMAX network with reduced MIMO capability during certain intervals and with maximum MIMO capability during other intervals. 1004). Further, while the MS 1002 performs certain functions related to the BS 1006 of the second RAT, the MS 1002 can communicate with the BS 1004 of the WiMAX network with reduced MIMO capability during successive intervals. .

Various operations of the methods described above may be performed by any suitable means capable of performing the corresponding functions. The means may include various hardware and / or software component (s) and / or module (s), including but not limited to circuits, application specific semiconductors (ASICs) or processors. In general, the operations shown in the figures are presented herein and these operations may have corresponding counterpart means + functional components having similar numbers. For example, blocks 602-608 and 802-804 shown in FIGS. 6 and 8 may correspond to blocks 702-708 and 902-908 shown in FIGS. 7 and 9.

As used herein, the term “determining” includes various operations. For example, "determining" means "calculating", "computing", "processing", "inducing", "investigating", "looking up" (e.g., Search in a table, database, or other data structure), 'ascertaining', and the like. In addition, “determining” may include “receiving” (eg, receiving information), “accessing” (eg, accessing data in memory), and the like. Also, “determining” may include “resolving”, “selecting and choosing”, “establishing”, and the like.

Various operations of the methods described above may be performed by any suitable means capable of performing the operations, such as various hardware and / or software component (s), circuits, and / or module (s). In general, any of the operations shown in the figures may be performed by corresponding functional means capable of performing the operations.

Various example logic blocks, modules, and circuits described in connection with the present disclosure may be used in general purpose processors, digital signal processors (DSPs), application specific semiconductors (ASICs), field programmable gate arrays (FPGAs), or other programmable logic devices. (PLD), discrete gate or transistor logic, discrete hardware components, or any combination designed to implement the functions described herein. A general purpose processor may be a microprocessor, and in the alternative, the processor may be a conventional processor, controller, microcontroller, or state machine. A processor may be implemented as a combination of computing devices such as, for example, a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or a combination of these configurations.

The steps of an algorithm or method described in connection with the aspects disclosed herein may be implemented directly in hardware, in a software module executed by a processor, or by a combination of the two. The software modules exist as any form of known storage medium. Some examples of storage media that can be used include RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, portable disk, CD-ROM, and the like. A software module can include a single instruction, or multiple instructions, and can be distributed through various different code segments, between different programs and across multiple storage media. The storage medium may be coupled to the processor such that the processor can read information from the storage medium and write information to the storage medium. In the alternative, the storage medium may be integral to the processor.

The methods disclosed herein comprise one or more steps or actions for achieving the described methods. The steps and / or actions of the methods may be interchangeable with other inventions without departing from the scope of the invention. In other words, unless a specific order of steps or actions is specified, the order and / or use of specific steps and / or actions may be modified without departing from the scope of the present invention.

The functions presented may be implemented through hardware, software, firmware, or a combination thereof. If implemented in software, the functions may be stored as one or more instructions on a computer-readable medium. Computer readable media can be any available media that can be accessed by a computer. For example, such computer readable media may be program code required in the form of RAM, ROM, EEPROM, CD-ROM or other optical disk storage media, magnetic disk storage media or other magnetic storage devices, or instructions or data structures. And any other media that can be used to store and carry the computer and that can be accessed by a computer. Disks and discs used herein include compact discs (CDs), laser discs, optical discs, DVDs, floppy disks, and Blu-ray discs, where the disks magnetically reproduce data, but the discs are optically To play the data.

Thus, certain aspects may comprise a computer program product for performing the operations presented herein. For example, such computer program product may include a computer-readable medium having stored instructions, which instructions are executed by one or more processors to perform the operations described herein. In certain aspects, the computer program product may include a packaging material.

The software or commands may also be transmitted via a transmission medium. For example, if the software is transmitted from a website, server, or other remote source using wireless technologies such as coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or infrared radio, and microwave. Wireless technologies such as coaxial cable, fiber optic cable, twisted pair, DSL, or infrared radio, and microwave may be included within the definition of such media.

In addition, modules and / or other suitable means for performing the methods and techniques described herein may be downloaded by the corresponding user terminal and / or base station and / or otherwise by the user terminal and / or base station It should be understood that it can be obtained. For example, such a device may be coupled to a server to facilitate the transfer of means for performing the methods described herein. Alternatively, the various methods described herein may be provided via storage means (eg, physical storage media such as random access memory (RAM), read-only memory (ROM), compact disk (CD) or floppy disk, etc.). The user terminal and / or base station may obtain various methods when providing or connecting the storage means to the device. In addition, any other suitable technique for providing the methods and techniques described herein to a device can be used.

It is to be understood that the claims are not limited to the precise configuration and components shown above. Various modifications, variations, and variations may be made within the arrangement, operation, and details of the apparatus, methods, and systems described herein without departing from the scope of the claims.

Although the foregoing description is directed to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof, and the scope of the present invention is defined below. Determined by them.

Claims (32)

A method for communicating using a first radio access technology (RAT) and a second RAT, the method comprising:
Sending a request message to a base station (BS) of the first RAT indicating an indicating set of multiple-input multiple-output (MIMO) resources for reallocation;
During a scan duration, communicating with the BS of the first RAT using non-reallocated MIMO resources, and communicating with the BS of the second RAT using reallocated MIMO resources ; And
During a normal duration, communicating with the BS of the first RAT using the reallocated MIMO resources and the unallocated MIMO resources;
A method for communicating using a first RAT and a second RAT. The method of claim 1,
The first RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
A method for communicating using a first RAT and a second RAT. The method of claim 1,
The step of transmitting to the base station BS of the first RAT a request message indicating a set of MIMO resources for reallocation,
Sending a mobile scan request message indicating the set of MIMO resources for reallocation;
A method for communicating using a first RAT and a second RAT. The method of claim 1,
Wherein the second RAT comprises a code division multiple access (CDMA) RAT;
A method for communicating using a first RAT and a second RAT. As a method for communicating with a mobile station (MS),
Receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation;
During a scan duration, communicating with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And
During normal duration, communicating with the MS in a second transmission mode assuming the use of the reallocated and unallocated MIMO resources by the MS;
Method for communicating with a mobile station (MS). 6. The method of claim 5,
The RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
Method for communicating with the MS. 6. The method of claim 5,
The step of receiving by the BS of the RAT a request message indicating a set of MIMO resources of the MS for reallocation,
Receiving a mobile scan request message indicating the set of MIMO resources for reallocation;
Method for communicating with the MS. 6. The method of claim 5,
Wherein the first and second transmission modes have different corresponding data rates,
Method for communicating with the MS. An apparatus for communicating using a first radio access technology (RAT) and a second RAT, the apparatus comprising:
Logic for transmitting a request message to a base station (BS) of the first RAT indicating a set of multiple-input multiple-output (MIMO) resources for reallocation;
During scan duration, logic for communicating with the BS of the first RAT using unallocated MIMO resources and communicating with the BS of the second RAT using reallocated MIMO resources; And
During normal duration, logic for communicating with the BS of the first RAT using the reallocated MIMO resources and the unallocated MIMO resources;
And apparatus for communicating using the first RAT and the second RAT. The method of claim 9,
The first RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
And apparatus for communicating using the first RAT and the second RAT. The method of claim 9,
The logic for transmitting a request message to the BS of the first RAT indicating a set of MIMO resources for reallocation,
And transmit a mobile scan request message indicating the set of MIMO resources for reallocation.
And apparatus for communicating using the first RAT and the second RAT. The method of claim 9,
Wherein the second RAT comprises a code division multiple access (CDMA) RAT;
And apparatus for communicating using the first RAT and the second RAT. An apparatus for communicating with a mobile station (MS),
Logic for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation;
During scan duration, logic to communicate with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And
During normal duration, logic for communicating with the MS in a second transmission mode assuming the use of reallocated and unallocated MIMO resources by the MS;
A device for communicating with a mobile station (MS). The method of claim 13,
The RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
A device for communicating with a mobile station (MS). The method of claim 13,
The logic for receiving, by the BS of the first RAT, a request message indicating a set of MIMO resources of the MS for reallocation,
Configured to receive a mobile scan request message indicating the set of MIMO resources for reallocation;
A device for communicating with a mobile station (MS). The method of claim 13,
Wherein the first and second transmission modes have different corresponding data rates,
A device for communicating with a mobile station (MS). An apparatus for communicating using a first radio access technology (RAT) and a second RAT, the apparatus comprising:
Means for transmitting a request message to a base station (BS) of the first RAT indicating a set of multiple-input multiple-output (MIMO) resources for reallocation;
During scan duration, means for communicating with the BS of the first RAT using unallocated MIMO resources and with the BS of the second RAT using reallocated MIMO resources; And
During normal duration, means for communicating with the BS of the first RAT using the reallocated MIMO resources and the unallocated MIMO resources;
And apparatus for communicating using the first RAT and the second RAT. The method of claim 17,
The first RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
And apparatus for communicating using the first RAT and the second RAT. The method of claim 17,
The means for transmitting to the BS of the first RAT a request message indicating a set of MIMO resources for reallocation;
And transmit a mobile scan request message indicating the set of MIMO resources for reallocation.
And apparatus for communicating using the first RAT and the second RAT. The method of claim 17,
Wherein the second RAT comprises a code division multiple access (CDMA) RAT;
And apparatus for communicating using the first RAT and the second RAT. An apparatus for communicating with a mobile station (MS),
Means for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation;
During scan duration, means for communicating with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And
During normal duration, means for communicating with the MS in a second transmission mode assuming use of reallocated and unallocated MIMO resources by the MS;
A device for communicating with a mobile station (MS). The method of claim 21,
The first RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
A device for communicating with a mobile station (MS). The method of claim 21,
Means for receiving, by a BS of a first RAT, a request message indicating a set of MIMO resources of the MS for reallocation,
Configured to receive a mobile scan request message indicating the set of MIMO resources for reallocation;
A device for communicating with a mobile station (MS). The method of claim 21,
Wherein the first and second transmission modes have different corresponding data rates,
A device for communicating with a mobile station (MS). A computer-program storage device for communicating using a first radio access technology (RAT) and a second RAT, comprising:
The computer-program storage device includes a computer readable medium having a set of stored instructions that can be executed by one or more processors, the set of instructions:
Instructions for sending a request message to a base station (BS) of the first RAT indicating a set of multiple-input multiple-output (MIMO) resources for reallocation;
During scan duration, instructions for communicating with the BS of the first RAT using unallocated MIMO resources and with the BS of the second RAT using reallocated MIMO resources; And
During normal duration, instructions for communicating with a BS of the first RAT using the reallocated MIMO resources and the unallocated MIMO resources;
Computer-Program Storage. The method of claim 25,
The first RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
Computer-Program Storage. The method of claim 25,
The instructions for sending a request message to the BS of the first RAT indicating a set of MIMO resources to reallocate,
Instructions for transmitting a mobile scan request message indicating the set of MIMO resources for reallocation;
Computer-Program Storage. The method of claim 25,
Wherein the second RAT comprises a code division multiple access (CDMA) RAT;
Computer-Program Storage. A computer-program storage device for communicating with a mobile station (MS),
The computer-program storage device includes a computer readable medium having a set of stored instructions that can be executed by one or more processors, the set of instructions:
Instructions for receiving, by a base station (BS) of a radio access technology (RAT), a request message indicating a set of multiple-input multiple-output (MIMO) resources of the MS for reallocation;
During a scan duration, instructions for communicating with the MS in a first transmission mode assuming use of only unallocated MIMO resources by the MS; And
During normal duration, instructions for communicating with the MS in a second transmission mode assuming the use of reallocated and unallocated MIMO resources by the MS;
Computer-Program Storage. 30. The method of claim 29,
The RAT is,
In accordance with one or more of the standards of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards,
Computer-Program Storage. 30. The method of claim 29,
The instructions for receiving, by a BS of a RAT, a request message indicating a set of MIMO resources of the MS for reallocation,
Instructions for receiving a mobile scan request message indicating the set of MIMO resources for reallocation;
Computer-Program Storage. 30. The method of claim 29,
Wherein the first and second transmission modes have different corresponding data rates,
Computer-Program Storage.

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